Do the right order in levels with 8, 9, or 10+ enemies. There are only few levels where you can get them, and of course the orders are hard because you have to kill so many enemies in the exact order.
In my view, 97 is one of the easiest of these levels. Usually takes one life, but I will gladly sacrifice that life for more than 200k points there

Others are

: 64, 15.5, 43.7, 47 (these are at least beatable...

: 43.5, 46.1, 15.6

: Don't know... There is one somewhere in Hell where you can easily get it in 2p mode. I don't know about any normal level where you can really get it without

.